Many early spring flowering trees and shrubs begin to break out of dormancy in late February. However, gardeners often miss the beautiful tree or shrub flower show because they pruned too early. Early spring flowering plants develop blooms on old wood (that is, they formed flower bud initials during the previous year’s growing season) and pruning them in winter removes these flower buds. Therefore, to prevent removing flower buds too soon, wait to prune until AFTER all flowers have faded.
Shade trees and large shrubs that are not grown for a flower display can be pruned in late February. Using proper pruning techniques prevents damaging trees and shrubs. If limbs are larger than 1-1/2 inches in diameter or heavily weighted, use the three-step method for removal (see Figure 1). The first cut is made on the underside of the limb about 6 inches away from the trunk but only cut about one-third of the way through the limb. The second cut is made starting on the top side of the limb at 3 to 6 inches beyond the first cut. Cut completely through the tree limb. The third and final cut is made just outside the branch collar, which is a rough, swollen area surrounding the base of the limb. Complete the cut by following along the outside of the branch collar.
Remember when pruning to remove dead or diseased branches first, and then take out any rubbing or crossed branches. Lastly, complete the pruning to maintain a natural form, unless formality is appropriate for the landscape design.
For more information, see HGIC1003, Principles and Practices for Pruning Trees, HGIC 1053, Pruning Shrubs and HGIC Hot Topic, The Art & Science of Pruning.